﻿using Newtonsoft.Json.Bson;
using Newtonsoft.Json.Utilities;
using System;
using System.Globalization;

namespace Newtonsoft.Json.Converters
{
    /// <summary>
    /// Converts a <see cref="T:Newtonsoft.Json.Bson.BsonObjectId" /> to and from JSON and BSON.
    /// </summary>
    public class BsonObjectIdConverter : JsonConverter
    {
        /// <summary>
        /// Writes the JSON representation of the object.
        /// </summary>
        /// <param name="writer">The <see cref="T:Newtonsoft.Json.JsonWriter" /> to write to.</param>
        /// <param name="value">The value.</param>
        /// <param name="serializer">The calling serializer.</param>
        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
        {
            BsonObjectId bsonObjectId = (BsonObjectId)value;
            BsonWriter bsonWriter = writer as BsonWriter;
            if (bsonWriter != null)
            {
                bsonWriter.WriteObjectId(bsonObjectId.Value);
                return;
            }
            writer.WriteValue(bsonObjectId.Value);
        }

        /// <summary>
        /// Reads the JSON representation of the object.
        /// </summary>
        /// <param name="reader">The <see cref="T:Newtonsoft.Json.JsonReader" /> to read from.</param>
        /// <param name="objectType">Type of the object.</param>
        /// <param name="existingValue">The existing value of object being read.</param>
        /// <param name="serializer">The calling serializer.</param>
        /// <returns>The object value.</returns>
        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
        {
            if (reader.TokenType != JsonToken.Bytes)
            {
                throw new JsonSerializationException("Expected Bytes but got {0}.".FormatWith(CultureInfo.InvariantCulture, reader.TokenType));
            }
            return new BsonObjectId((byte[])reader.Value);
        }

        /// <summary>
        /// Determines whether this instance can convert the specified object type.
        /// </summary>
        /// <param name="objectType">Type of the object.</param>
        /// <returns>
        /// 	<c>true</c> if this instance can convert the specified object type; otherwise, <c>false</c>.
        /// </returns>
        public override bool CanConvert(Type objectType)
        {
            return objectType == typeof(BsonObjectId);
        }
    }
}
